Merge branch 'stable'

Conflicts:
	src/rabbit_exchange.erl

3 files changed, 174 insertions, 1 deletions

diff --git a/src/rabbit.erl b/src/rabbit.erl
index 8498e54c09..1f8181dafd 100644
--- a/src/rabbit.erl
+++ b/src/rabbit.erl
@@ -213,6 +213,12 @@
                                    [background_gc]}},
                     {enables,     networking}]}).
 
+-rabbit_boot_step({rabbit_core_metrics_gc,
+                   [{description, "background core metrics garbage collection"},
+                    {mfa,         {rabbit_sup, start_restartable_child,
+                                   [rabbit_core_metrics_gc]}},
+                    {enables,     networking}]}).
+
 %%---------------------------------------------------------------------------
 
 -include("rabbit_framing.hrl").
diff --git a/src/rabbit_core_metrics_gc.erl b/src/rabbit_core_metrics_gc.erl
new file mode 100644
index 0000000000..e7f848bbc3
--- /dev/null
+++ b/src/rabbit_core_metrics_gc.erl
@@ -0,0 +1,164 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is GoPivotal, Inc.
+%% Copyright (c) 2007-2017 Pivotal Software, Inc.  All rights reserved.
+%%
+-module(rabbit_core_metrics_gc).
+
+-record(state, {timer,
+                interval
+               }).
+
+-spec start_link() -> rabbit_types:ok_pid_or_error().
+
+-export([start_link/0]).
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2,
+         code_change/3]).
+
+start_link() ->
+    gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
+
+init(_) ->
+    Interval = rabbit_misc:get_env(rabbit, core_metrics_gc_interval, 120000),
+    {ok, start_timer(#state{interval = Interval})}.
+
+handle_call(test, _From, State) ->
+    {reply, ok, State}.
+
+handle_cast(_Request, State) ->
+    {noreply, State}.
+
+handle_info(start_gc, State) ->
+    gc_connections(),
+    gc_channels(),
+    gc_queues(),
+    gc_exchanges(),
+    gc_nodes(),
+    gc_gen_server2(),
+    {noreply, start_timer(State)}.
+
+terminate(_Reason, #state{timer = TRef}) ->
+    erlang:cancel_timer(TRef),
+    ok.
+
+code_change(_OldVsn, State, _Extra) ->
+    {ok, State}.
+
+start_timer(#state{interval = Interval} = St) ->
+    TRef = erlang:send_after(Interval, self(), start_gc),
+    St#state{timer = TRef}.
+
+gc_connections() ->
+    gc_process(connection_created),
+    gc_process(connection_metrics),
+    gc_process(connection_coarse_metrics).
+
+gc_channels() ->
+    %% TODO channel stats
+    gc_process(channel_created),
+    gc_process(channel_metrics),
+    gc_process(channel_process_metrics),
+    ok.
+
+gc_queues() ->
+    Queues = rabbit_amqqueue:list_names(),
+    GbSet = gb_sets:from_list(Queues),
+    gc_entity(queue_metrics, GbSet),
+    gc_entity(queue_coarse_metrics, GbSet),
+    gc_process_and_entity(channel_queue_metrics, GbSet),
+    gc_process_and_entity(consumer_created, GbSet),
+    ExchangeGbSet = gb_sets:from_list(rabbit_exchange:list_names()),
+    gc_process_and_entities(channel_queue_exchange_metrics, GbSet, ExchangeGbSet).
+
+gc_exchanges() ->
+    Exchanges = rabbit_exchange:list_names(),
+    GbSet = gb_sets:from_list(Exchanges),
+    gc_process_and_entity(channel_exchange_metrics, GbSet).
+
+gc_nodes() ->
+    Nodes = rabbit_mnesia:cluster_nodes(all),
+    GbSet = gb_sets:from_list(Nodes),
+    gc_entity(node_node_metrics, GbSet).
+
+gc_gen_server2() ->
+    gc_process(gen_server2_metrics).
+
+gc_process(Table) ->
+    ets:foldl(fun({Pid = Key, _}, none) ->
+                      gc_process(Pid, Table, Key);
+                 ({Pid = Key, _, _, _}, none) ->
+                      gc_process(Pid, Table, Key)
+              end, none, Table).
+
+gc_process(Pid, Table, Key) ->
+    case erlang:is_process_alive(Pid) of
+        true ->
+            none;
+        false ->
+            %% TODO catch?
+            ets:delete(Table, Key),
+            none
+    end.
+
+gc_entity(Table, GbSet) ->
+    ets:foldl(fun({{_, Id} = Key, _}, none) ->
+                      gc_entity(Id, Table, Key, GbSet);
+                 ({Id = Key, _}, none) ->
+                      gc_entity(Id, Table, Key, GbSet);
+                 ({Id = Key, _, _, _, _}, none) ->
+                      gc_entity(Id, Table, Key, GbSet)
+              end, none, Table).
+
+gc_entity(Id, Table, Key, GbSet) ->
+    case gb_sets:is_member(Id, GbSet) of
+        true ->
+            none;
+        false ->
+            %% TODO catch?
+            ets:delete(Table, Key),
+            none
+    end.
+
+gc_process_and_entity(Table, GbSet) ->
+    ets:foldl(fun({{Pid, Id} = Key, _, _, _, _, _, _}, none)
+                  when Table == channel_queue_metrics ->
+                      gc_entity(Id, Table, Key, GbSet),
+                      gc_process(Pid, Table, Key);
+                 ({{Pid, Id} = Key, _, _, _}, none)
+                    when Table == channel_exchange_metrics ->
+                      gc_entity(Id, Table, Key, GbSet),
+                      gc_process(Pid, Table, Key);
+                 ({{Id, Pid, _} = Key, _, _, _, _}, none)
+                    when Table == consumer_created ->
+                      gc_entity(Id, Table, Key, GbSet),
+                      gc_process(Pid, Table, Key);
+                 ({{{Pid, Id}, _} = Key, _, _, _, _}, none) ->
+                      gc_process_and_entity(Id, Pid, Table, Key, GbSet)
+              end, none, Table).
+
+gc_process_and_entity(Id, Pid, Table, Key, GbSet) ->
+    case erlang:is_process_alive(Pid) orelse gb_sets:is_member(Id, GbSet) of
+        true ->
+            none;
+        false ->
+            %% TODO catch?
+            ets:delete(Table, Key),
+            none
+    end.
+
+gc_process_and_entities(Table, QueueGbSet, ExchangeGbSet) ->
+    ets:foldl(fun({{Pid, {Q, X}} = Key, _}, none) ->
+                      gc_process(Pid, Table, Key),
+                      gc_entity(Q, Table, Key, QueueGbSet),
+                      gc_entity(X, Table, Key, ExchangeGbSet)
+              end, none, Table).
diff --git a/src/rabbit_exchange.erl b/src/rabbit_exchange.erl
index 85f061a17b..7a3f194e01 100644
--- a/src/rabbit_exchange.erl
+++ b/src/rabbit_exchange.erl
@@ -23,7 +23,7 @@
          lookup/1, lookup_or_die/1, list/0, list/1, lookup_scratch/2,
          update_scratch/3, update_decorators/1, immutable/1,
          info_keys/0, info/1, info/2, info_all/1, info_all/2, info_all/4,
-         route/2, delete/3, validate_binding/2]).
+-export([list_names/0]).
 %% these must be run inside a mnesia tx
 -export([maybe_auto_delete/2, serial/1, peek_serial/1, update/2]).
 
@@ -61,6 +61,7 @@
         (name()) -> rabbit_types:exchange() |
                     rabbit_types:channel_exit().
 -spec list() -> [rabbit_types:exchange()].
+-spec list_names() -> [rabbit_exchange:name()].
 -spec list(rabbit_types:vhost()) -> [rabbit_types:exchange()].
 -spec lookup_scratch(name(), atom()) ->
                                rabbit_types:ok(term()) |
@@ -261,6 +262,8 @@ lookup_or_die(Name) ->
 
 list() -> mnesia:dirty_match_object(rabbit_exchange, #exchange{_ = '_'}).
 
+list_names() -> mnesia:dirty_all_keys(rabbit_exchange).
+
 %% Not dirty_match_object since that would not be transactional when used in a
 %% tx context
 list(VHostPath) ->